Field of the Invention
The invention relates to a method for controlling constant air volume of an electronically commutated motor (ECM motor) in a heating, ventilating, and air conditioning (HVAC) system.
Description of the Related Art
Typically, an air flowmeter is directly installed in the air duct of the air conditioning system to obtain constant air volume. The method increases the production cost and the air flowmeter often malfunctions, thus causing control failure. Other methods for controlling the constant air volume require monitoring the static pressure of the system to adjust the rotational speed, or require strong computing capacity of the MCU of the motor controller, all of which increase the production cost.